In an image forming apparatus such as a multi function peripheral (MFP) equipped with a plurality of functions including printing, copying, scanning, data generated by jobs executed using those functions are stored in a storing section such as an HDD (Hard Disk Drive) for a purpose of reuse and the like. A job managing apparatus for managing jobs of the image forming apparatus manages the status of the HDD, and secures, when the amount of usage of the HDD has been increasing, the amount of free storage of the HDD by deleting unnecessary jobs or other ways. In such occasions, when having no information of the free storage capacity of the HDD, the image forming apparatus hardly judges whether to delete data of jobs or not; thus, there are proposed various methods to simply display the amount of usage of the HDD and the amount of free storage of the HDD for easy judgment.
For example, Japanese Laid-Open Patent Application Publication (JP-A) No. 2003-078687 discloses, with respect to an image forming apparatus, that if the amount of free storage of a HDD is greater than a predetermined value, the amount of free storage is displayed in percentage and if the amount of free storage is smaller than the predetermined value, the amount of free storage is displayed in number of sheets. The document also describes that the amount of free storage of the HDD is displayed for each image forming conditions including color modes (full color, black-and-white, and the like) and image forming sizes (A3, A4, and the like).
This is not a technique related to a printing system, but JP-A No. 2003-009048 discloses, as a technique related to storing broadcast programs in a program recording apparatus, that the amount of free storage of a HDD is displayed in percentage, that the list of data already stored in the HDD is displayed on the same display screen, and that there is displayed a numerical value indicating what percentage of the data to be stored now can be stored in case that those stored data are deleted.
In addition, as a technique related to storing data in cameras, JP-A No. 2009-171395 discloses a system configured to send image data to a server and store the data into a HDD of the server. The system displays a bar of the unsendable data size and the sendable data size and a bar of the amount of usage of the HDD and the amount of free storage of the HDD, and changes, when an user has performed an operation of increasing the amount of free storage of the HDD while watching the list on the same screen, the contents of the bars.
However, with the method in which the amount of usage and the amount of free storage of a HDD are displayed in percentage or in number of sheets as shown in JP-A No. 2003-078687 and No. 2003-009048, it is difficult to intuitively grasp the amount of usage and the amount of free storage of the HDD. On the other hand, in the case that the amount of usage and the amount of free storage of a HDD are displayed as shown in JP-A No. 2009-171395, it is possible to intuitively grasp the amount of usage and the amount of free storage of the HDD. However, JP-A No. 2009-171395 is a technique related to cameras, and the bar of the amount of usage and the amount of free storage of a HDD is not displayed for each job; thus, it is difficult to decide which job data should be deleted.
In particular, since a HDD in an image forming apparatus stores various kinds of job data including print data (written in PDL (Page Description Language) such as PCL (Printer Control Language) and PS (Post Script)) sent from clients, image data generated by rasterizing these print data, image data read in by a scanning function, and form data, it is difficult to decide which job data to delete unless the amount of usage and the amount of free storage of a HDD are displayed based on proper sorting of those data.
Further, since an image forming apparatus stores various kinds of job data as described above, an image forming apparatus is equipped with a plurality of HDDs (or the HDD is divided into a plurality of areas), and stores data used by the engine executing printing process and data used by the controller executing image processing in different HDDs, for example. Thus, unless the amount of usage and the amount of free storage is displayed for each HDD, it is difficult to decide which piece of the job data stored in the HDDs should be deleted.
Further, for deleting job data stored in a HDD, it is necessary to display a list of jobs stored in the HDD and to confirm details of each job on the list; however, if the display of the amount of usage and the amount of free storage of the HDD and the list of the jobs are displayed on different screens, which make a user difficult to recognize which job should be deleted. As the result, it may cause a wrong operation such as deleting job data which does not need to be deleted, whereby there will be caused a problem that the operations for deleting job data becomes complex. The present invention seeks to solve the problem.